I’m taking advantage of the current NASA mania to ask for some help. Can anyone tell us what’s going on with all the equating in this picture from the Bert Brandt photo collection in the HMRC (MSS0087-2488 for those of you keeping score at home)?
Bonus: Grand Coulee Dam. Un-freaking-believable. (I’ll be home and back on duty sometime next week.)
I might have been able to understand that math when I was still at Rice, but those brain cells are long gone.
I’ll guess that the third one up is Time(at ignition) = Time(at impact) minus something complicated.
So now you have an idea of why I spent over 40 years with the US Army Corps of Engineers, designing dams and powerhouses.
I sure do! I was just blown away.
And also why, although I was admitted as an S-E Math major in 1956, I decided that was not going to work after about one day. I endured more then enough math courses while pursuing my B. S. in M. E.
Probably the equations for landing the thing. I searched for “r double dot” and found that is shorthand for the the second derivative with respect to time, which is another way to say “acceleration”. The line over the top is often shorthand for a vector.
http://mathworld.wolfram.com/DoubleDot.html
With a lightweight rocket, the acceleration changes when the thrust stays the same because the craft is lighter as fuel is consumed. So the basic thrust vs weight calculation depends on the history of the thrust up to that point. I’m sure that is all basic and boring to actual rocket engineers.
That seems to be correct, Walter. Due to the angle I cannot see all of the work ( and to say my vector calculus is rusty would be an undeserved compliment) but there are symbols for time of ignition and vectors for accelerations as well. The cross product is there as well but as I said rusty would be too kind.
If you want to find out more about the Columbia River System, BPA (Bonneville Power Administration) has a nice history site at https://www.bpa.gov/news/AboutUs/History/Pages/default.aspx.
And yes, the engineering work is awesome.
William, does the Corp have a site showing the history of some of these projects?
Awesome is the right word. I’m still thinking about it days later,
According to the caption for the copy I saw, it’s the formula for sending the appolo capsule to the moon and back.